Electric vehicles (EVs) have become fixtures in the car market, both in the U.S. and abroad, but there are hurdles to mass consumer adoption. In addition to continuing to be cost prohibitive to many, EV technology is still in need of advancements in efficiency, particularly at typical performance levels.
As of December 2014, the United States possesses the largest fleet of plug-in electric vehicles in the world, with 291,332 highway capable plug-in electric cars sold since the launch of the Tesla Roadster in 2008. In 2013, the U.S. Department of Energy launched the “EV Everywhere Grand Challenge,” a program designed to spur advancement in electric vehicle technology.
Dr. Daniel Costinett’s JDRD team has taken up this challenge with a project that seeks to improve the performance of EVs at standard use levels by working on a new DC-DC drive train system through the design of a new power converter. Costinett’s team is taking elements of two currently existing power converters and merging them into a single new system, a design that will be cheaper, smaller and more efficient.
“Right now, everything is built to the worst case scenario,” says Costinett. “They’re efficient at full power and full speed, but when you get back to more typical use, the efficiency decreases.”
The converter is being designed with an eye toward creating better results for typical use, while maintaining effective functionality at maximum use. Costinett’s new configuration should also allow the system to continue operating in the event of converter failure. The team’s goal is to create a converter which is both 25% smaller and 40% lower in cost than the current state-of-the-art technology, while reducing total energy losses by 30%.
Costinett’s JDRD team is currently working with new materials for transistors, which have traditionally been made with silicon, and has created a scaled down converter prototype for testing, which is yielding promising results. The advances generated by this project could potentially lead to a breakthrough in the electric vehicle cost-performance ratio and facilitate future collaborations between UT and ORNL teams.